The present application relates generally to an improved method and apparatus for continuously applying multiple strips of continuous fiber tape to form various laminated structural articles and, more particularly, to doing so with a resin prepreg tape in a more simple and effective manner.
In a co-pending application, issued as U.S. Pat. No. 7,063,118 to David E. Hauber, James P. Martin, Michael J. Pasanen, Robert J. Langone and Scott F. Miller which is also assigned to the present assignee, there is described a novel method and apparatus to reinforce various structural shapes with single strips of prepreg tape also being applied in a single direction. To reverse or change the tape laying direction with said apparatus generally requires rotation of the tape laying head or returning the tape laying head to the original start position in order to deposit additional reinforcement tape on the structural shape. Such interruption of the tape laying procedure limits throughput of the tape being applied as well as complicates the equipment and control means being needed for unproductive apparatus movement. Said already known method and apparatus employs continuous fibers selected from the group consisting of ceramics, metals, carbon, glass compositions and organic polymers which has been preimpregnated with a resin binder and further provided with a releasable backing layer. In applying said tape, the disclosed automated apparatus employs a laterally moving head member having a novel cut and restart mechanism enabling the tape to be cut while still being fed after removal of the customary backing layer. The disclosed tape laying head member applies the unbacked reinforcement tape to the surface of the structural shape being laminated with conventional compact roller means, said head member further having a pair of operationally cooperating mechanisms to first strip the backing layer from the composite tape while being fed to the structural shape surface and thereafter sever a predetermined length of the unbacked tape from the tape supply spool while still being continuously transported in the apparatus. The backing removal mechanism in the disclosed apparatus includes means enabling separation of the backing layer from the moving tape while further accumulating the removed backing layer in the apparatus with a motor driven return spool. The disclosed tape laying head member still further includes mechanical cutter means which cooperate operationally with pinch roller means enabling forward tape movement when being fed while preventing backward tape movement during tape severance with said cutter means. Conventional associated electrical control means in the disclosed apparatus operates said head member in a preprogrammed sequential manner.
The above disclosed method and apparatus to automatedly laminate various structural shapes in said manner with multiple layers of continuous fibers preimpregnated with a resin binder still remains unduly complex and expensive. Tape laydown in said manner has been found to be relatively slow and require process interruption which understandably increases the cost of manufacture. Moreover, the size and complexity of said apparatus for tape laydown causes excessive downtime to be experienced during continuous equipment operation. Minimizing or eliminating such observed disadvantages found with the above disclosed method and apparatus for tape laydown would thereby prove beneficial in reducing manufacturing costs for the resulting laminated article.
It is an important object of the present invention, therefore, to provide a novel apparatus enabling multi-directional tape laydown in an improved automated manner.
It is still another important object of the present invention to provide a novel method for multi-directional tape laydown.
Still another important object of the present invention is to provide a novel automated tape laying apparatus enabling multiple strips of the reinforcement tape to be concurrently applied.
A still further object of the present invention is to provide a novel method for concurrent deposition of multiple reinforcement tape strips.
These and still further objects of the present invention will become more apparent upon considering the following more detailed description of the present invention.